Allocate is a tower-defense game heavily inspired by the original Command & Conquer: Tiberian Dawn. Like later games in the series, you can divert power between structures to use it where it's needed most.
In addition, you can also click-and-drag from your turrets to manually target distant enemies. In the meantime, you must also consider powering a Mine to collect resources and the Spaceport to save as many refugees as you can!